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(No'Mode'L) J. W. HYATT. PROCESS OF DRYING SHEETS 0F PLASTIC MATERIAL.

No. 254,439. Patented Feb. 28,1882.

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N. PETERS. Piwlo-Litfwgnphcr. Withinglm D.C.

- UNITED STATES PATENT, OF I E,

I JOHN W. HYATT, OF NEWARK, NEW JERSEY, ASSIGNOR TO THE OELLULOID MANUFACTURING COMPANY, OF NEW YORK, N. Y.

PROCESS OF DRYING SHEETS OF PLASTIC MATERIAL,

SPECIFICATION forming part of Letters Patent No. 254,439, dated February 28, 1 882, Application filed Augnst23,1881. (No model.) i

To all whom tt may concern .Be it known that I, JOHN W. HYA'IT, of Newark, in the county of Essex and State of New Jersey, have invented a new and useful Improvement in Processes ofDrying Sheets or Rolls of Plastic Material, of which the followin g is a specification, reference being had to the accompanying drawing.

The invention has relation to an improved process for drying sheets or rolls of plastic materials, and especially to provide a means for drying rolls or pieces of considerable length without cutting them, whereby a roll or piece analogous in form to a roll of wall-paper is produced.

I particularly contemplate the employment of my improved process in the treatment of the material known as celluloid and other compounds of pyroxyline.

My process consists in the employment of one or more drums or cylinders, upon which the sheet or piece is moved or rolled, being subjected to a proper tension to prevent the formation of wrinkles or creases,and being by preference inclosed in a heated compartment or drying-room, all as hereinafter more fully set forth. The tension mentioned will be sufficient to cause the sheet to dry with hard, smooth surfaces, and is necessarily different in its nature and eflect from that employed in drying any other material,itbein g specially regulated and adapted forthe requirements of a material having qualities and characteristics peculiar to itself.

The invention is especially useful in connection with the treatment of continuous pieces of compounds of pyroxyline formed by circumrasion or analogous means.

I contemplate the employment of appropriate machinery for the purpose of actuating the drum or drums, as hereinbefore set forth, and also propose to use such known methods of drying as may be adapted to facilitate the objects sought to be effected.

As far as 1 am aware sheets of plastic materialhave neverbeen successfully manufactured,

1 except according to the processes heretofore patented by me, by which the sheet is formed by being planed from a solidified slab or block,

"important purposes.

or by circumrasion from a cylinder. In the firstmentioned process one of the most important steps in the formation of the sheet consists .in providing a suitable means of drying the sheet to prevent the form ation of creases or wrinkles. It is obvious that the nature of a sheet of plastic material is such that unless some artificial means be provided to prevent the formation of creases and wrinkles during the period when it is being dried the sheet,when dried,will be comparatively valueless, except for relatively un- Where the sheet is not too large it may be eftectivelydried by being placed in proper frames; but where a continuous roll or pieceis formed by circumrasion this is not practicable, unless the sheet be cut, to avoid which is one of the chief objects of the invention.

In the accompanying-drawing I have shown mechanical appliances whereby the process may be satisfactorily practiced.

A denotes the drying case or compartment, in which are mounted the cylinders or drums B B, in the present instance two being employed.

The sheet ofmaterial is cut from a roll by circumrasion, so as to form a continuous piece, preferably by the machine patented to me June 25, 1878. The sheet as it passes from the cutting-machine may be run directly into the drying-case A; or it may be wound upon an auxilia-ry drum and transferred to the drying-case in that form, and afterward fed upon the cylinder B. In either event the end of the strip is first attached to the cylinder B, which is then re- "olved until the whole piece has been wound upon it, after which the free end of the piece is attached to the cylinder B, and the latter is given a movement in the contrary direction, so that when both cylinders are in motion the sheet will passfroni the upper side of one cylinder to the lower side of the other, or vice versa, thus securing the exposure of the greatest length of the piece between the cylinders, and causing the face of the strip wound inward on one cylinder to be on theoutside when on the other cylinder. After the strip has been wound on the cylinder B from the cylinder B the movement of the cylinders is immediately reversed,

be preferred.

The number of drying cylinders or drums employed is a matter of judgment, which will depend upon the circumstances, of the case.

It is obvious that'in lieu of the drum B a stick, 0, to hold the material may be used, as shown in Fig. 2. When this method is practiced the stick 0 will be rotated to take up the piece of material as fast as it is dried, forming it into a roll, and at the same time preserving the requisite tension to prevent the formation of creases or wrinkles.

The drums B B are so constructed that they may be revolved at a proper velocity by means of any convenient machinery, as will readily suggest itself to persons skilled in the art to which the invention relates. The motion of the drums will be adapted to the character of the material whichis to be treated, and the tension of the sheet will be such as to prevent the formation of wrinkles or other irregularities. The

size of the drums or cylinders, their adj ustment I do not limit myself to the employment ofany particular number of cylinders or drums,

or to anyparticular methods of using the same nor do I limit myself to the use of a drying 00m or case, although I prefer to employ one;

WhatI claim as my invention, and desire to secure by Letters Patent, is-

The process herein described of producing anddrying a sheet or continuous piece of plastic material of the nature of pyroxyline, which consists in first cutting the sheet from a roll or slab,and,second,movingthesame upon drums, the sheet being given a sufficient tension 'to cause it to dry with hard, smooth surfaces, and the movement being such as to permitthe sheet or piece to dry before the tension is discontinued, substantially as set forth.

In testimony that I claim the foregoing improvementin processes of drying sheets or rolls of plastic material, as above described, I have hereunto set my hand this 15th day of August, 1881.

J. W. HYATT.

Witnesses:

CHAS. G. GiLL, HERMAN GUsTow. 

